Extruded section and structures incorporating such section

ABSTRACT

An extruded structural member having a first pair of spaced apart flanges projecting from a face of the member and a second pair of spaced apart flanges projecting from another face of the member. The flanges are dimensioned such that one of the pairs will fit slidably between the other of the pairs on another member of similar configuration when connecting two such members together. Each flange of one of the pairs of flanges has a longitudinally extending ledge thereon, the ledges facing towards the member, and each flange of the other pair of flanges has a tab struck out therefrom and adjacent one end of the member providing an edge extending at an angle with respect to the ledges. In assembling two such members at an angle, the edges on one of the members engage with the ledges on another to hold the two members together in a predetermined angular relationship.

Elite States Patent [191 Hefner [451 Nov. 19, 1974 1 EXTRUDED SECTIONAND STRUCTURES INCORPORATING SUCH SECTION [75] Inventor: Joseph A.Hefner, Stoney Creek,

Ontario, Canada [22], Filed: July 3, 1972 [21] Appl. No.: 268,923

Related U.S. Application Data [63] Continuation-impart of Ser. No.192,425, Oct. 26,

1971, abandoned.

[30] Foreign Application Priority Data Feb. 7, 1972 Canada 134047 [52]U.S. C1 52/735, 52/738, 403/231 [51] int. Cl. E04c 3/07, E04b 1/343 [58]Field of Search 521730-732,

9 3963 665737191 3223; 49/DIG. 1; 403/230, 231, 242, 263

Edwards 52/731 3,216,170 11/1965 Deadrick 52/731 3,327,438 6/1967 Cooper52/731 3,339,334 9/1967 Rowan et al 52/731 3,562,992 2/1971 Kinsey52/731 3,604,176 9/1971 Campbell 52/735 FOREIGNPATENTS OR APPLICATIONS290,361 3/1967 Australia 52/731 653,664 l/l965 Belgium 8/1968 France52/731 Primary Examiner-John E. Murtagh Assistant ExaminerJames L.Ridgill, Jr.

Attorney, Agent, or Firm-Martin J. Marcus; A. W. Breiner 5 7] ABSTRACTAn extruded structural member having a first pair of spaced apartflanges projecting from a face of the member and a second pair of spacedapart flanges projecting from another face of the member. The flangesare dimensioned such that one of the pairs will fit slidably between theother of the pairs on another member of similar configuration whenconnecting two such members together. Each flange of one of the pairs offlanges has a longitudinally extending ledge thereon, the ledges facingtowards the member, and each flange of the other pair of flanges has atab struck out therefrom. and adjacent one end of the member providingan edge extending at an angle with respect to the ledges. In assemblingtwo such members at an angle, the edges on one of the members engagewith the ledges on another to hold the two members together in apredetermined angular relationship.

11 Claims, 12 Drawing Figures EXTRUDEI) SECTION AND STRUCTURESINCORPORATING SUCH SECTION This application is a continuation-in-part ofUS. Pat. application S. N. 192,425 filed Oct. 26, 1971, now abandoned.

The present invention relates to extruded sections and structuresincorporating extruded sections.

BACKGROUND OF THE INVENTION The use of extruded metal sections is nowcommon, and well known in many fields in view of the strength, rigidityand weight properties of the same. It has been a constant endeavour inthis particular field to provide such sections that are sufficientlyversatile to form various structures therefrom easily and quickly, withthe minimum of labour. It is accordingly highly desirable to provide anextruded section requiring minimum additional parts to join togethersecurely two or more such sections.

It has previously been known to fasten together extruded sections bymeans of a connecting part mounted SUMMARY OF THE INVENTION It is anobject of the present invention to provide an extruded structural memberwith a novel cross-section.

It is another object of the present invention to provide an extrudedstructural member with a crosssectional configuration whereby twomembers having the same cross-section can readily be interconnected withone another.

It is yet another object of the present invention to provide structurescomprising a plurality of extruded structural members, which members allhave the same crosssection and fit together with no need forinterconnecting parts.

In accordance with one aspect of the present invention, there isprovided a structural member constructed for connecting two such membersin a predetermined configuration such as a selected angle, andpreferably a right angle, to one another, said member comprising:

a. a pair of first flanges spaced apart from one another and projectingoutwardly from one face of said member and extending longitudinallytherealong, each of said first flanges having a longitudinally extendingfirst flange face directed towards the other of said flanges;

b. at least one second flange projecting from another face of saidmember and extending longitudinally along said member, said at least onesecond flange having a pair of longitudinally extending second flangefaces directed away from one another, the

first flange faces and the second flange faces having respectivespacings whereby said second flange fits between the pair of firstflanges of another similar structural member in assembling two suchstructural members; and first and second cooperating coupling portionslocated respectively on said first and second flanges, one of saidcoupling portions comprising two longitudinally extending ledges facingsaid member at a predetermined distance therefrom, and the other of saidcoupling portions comprising two edges disposed at a predetermineddistance from an end of said structural member and facing awaytherefrom, said respective first and second coupling portions beingdirected in opposite directions transverse to the respective first andsecond flanges for locking interengagement in an assembled position oftwo such members in said predetermined configuration.

In accordance with another aspect of the present invention, there isprovided an extruded structural member comprising:

a. a longitudinally extending first web;

b. a first flange means including a pair of first flanges spaced apartfrom one another and projecting outwardly from one face of said firstweb and extending longitudinally therealong, each of said first flangeshaving a longitudinally extending first flange face directed towards theother of said flanges, each of said first flange faces providing a ledgedefined by a discontinuity in said first flange face, said ledges facingsaid first web;

c. a second flange means including at least one second flange projectingfrom an opposite face of said web in a direction opposite to that ofsaid first flanges and extending longitudinally along said web, saidsecond flange means providing a pair of longitudinally extending secondflange faces directed away from one another, the first flange faces andthe second flange faces having respective spacings whereby said secondflange means fits between the pair of first flanges of the first flangemeans of another similar structural member in the assembly of two suchstructural members; and

d' a longitudinally extending second web connected to said first web andextending angularly away therefrom.

DESCRIPTION OF THE DRAWINGS The invention is illustrated by way ofexample in the accompanying drawings in which:

FIG. 1 is a general perspective view of a complete building structuresuch as a swimming pool enclosure constructed using extruded structuralmembers in accordance with the present invention;

FIGS. 2-7 are cross-sections of extruded structural members inaccordance with the present invention;

FIG. 8 is a perspective view showing the interconnection of twostructural elements, each of which is constructed of two extrudedstructural members in accordance with the present invention;

FIG. 9 is a cross-sectional view on theline 9-9 of FIG. 1;

FIG. I0 is a cross-section along the line [0-10 of FIG. 1;

FIG. 11 is a perspective view of a desk constructed of structuralmembers in accordance with the present invention; and

FIG. 12 is an exploded detail of a comer of the desk shown in FIG. 11.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to thedrawings, there is illustrated in FIG. 1, a structure which can bemanufactured simply and economically with a minimum of labour usingextruded members in accordance with the present invention and, in thisinstance, comprises a glazed enclosure for a swimming pool, hot house,cabin or the like. The structure is erected upon a foundation and twowhich is fastened base members 11, upon which are erected vertical studmembers 12 at selected spaced intervals. The stud members areinterconnected by sill members 13, and at the top by a plate 14 on whichrests a roof structure 15. The structural members of the presentinvention may be used as the roof rafters if desired. A door 16 and asliding window 17 are provided. The spaces between the sill members 13and plate members 14 are glazed with glass panes 18 while the portionsbetween the sill members 13 and the base members 11 are filled withtranslucent or other wall panels 19. v

Referring to FIG. 2, shown therein is a structural member 1 comprising alongitudinally extending web 20 with a first pair of spaced apartflanges 24 projecting from one face 20a of the web 20, at right anglesthereto, and a second flange 23 projecting from the opposite face 20b ofweb 20. Each of flanges 24 has two portions 24a and 24b, with portion24b extending between web 20 and portion 24a and being of less thicknessthan portion 24a. At the junction of its portions 24a and 24b, each ofthe flanges 24 has a ledge facing towards the web 20. As can be seenfrom the drawings, each of the two parallel outer mating faces 23b offlange 23 lies in substantially the same plane as a respective one ofthe inner mating faces 24c of the thicker portions 24a of flanges 24.This provides a close sliding fit of flange 23 between the flanges 24 ofanother, similar structural member in assembling together two suchmembers.

In the embodiment illustrated in FIG. 3, the flange 23 is replaced withtwo flanges 23 spaced apart from one another so as to be a close fitbetween flanges 24. There is included a second web 22 connected to anedge of web 20 and projecting perpendicularly away from web 20 toprovide a facing for the structural member.

In the embodiment of FIG. 4, the opposite faces of flange 23 are cutaway adjacent web 20 to provide two ledges 25 on flange 23 and flanges24 are of uniform thickness throughout their extent.

The embodiment shown in FIG. 5 includes the structure described withreference to FIG. 3 and further includes a web 21 extending parallel toweb 20 and spaced therefrom. Web 22 extends between and, is connectedto, respective edges of webs 20 and 21. A pair of spaced apart flanges23 are provided on web 21 and the flanges 23 of webs 20 and 21respectively extend in a direction towards one another with each flange23 on web 20 coplanar with a flange 23 on web 21. Additionally, each ofwebs 20 and 21 is provided, adjacent its free longitudinal edge, i.e.,that edge remote from web 22, with a track structure 26.

Each track structure comprises two spaced apart flanges 26a and 26b,projecting from the respective one of webs 20 and 21 in a directiontowards the other of webs 20 and 21. Flange 26a is of substantially flatconfiguration and flange 26b has two offset portions, so as to define asubstantially L-shaped longitudinally extending track therebetween.

The embodiment illustrated in FIG. 6 is similar to the embodimentdescribed with reference to FIG. 5 but with tracks 26 replaced by a web28 extending between webs 20 and 21, thus defining a hollow member ofrectangular cross-section. As will been seen from FIG. 6, the flanges 23on webs 20 and 21 extend inwardly of the hollow member and flanges 24 onweb 20 extend outwardly thereof. There is additionally provided a secondpair of flanges 24 extending outwardly from web 22, substantiallyperpendicular to the flanges 24 of web 20.

The embodiment shown in FIG. 7 is similar to that shown in FIG. 6 withthe second pair of flanges 24 being provided on web 21 rather than web22.

Referring to FIG. 8 there is shown two parallel structural members ofthe type shown in FIG. 5. The two members have their open sides facingtowards one another and are interconnected by an extruded thermallyinsulating member 27 which may be made of rubber or suitable plastic.The member 27 has two longitudinally extending spaced webs 27a, eachhaving portions of L- shaped cross-sectional configuration at itsrespective opposite edges. The L-shaped portions are each dimensioned toslide within the L-shaped track 26. The two webs 27a are interconnectedby two webs 27b, each of which has an offset portion centrally thereof,the offset is dimensioned such that the central portions of the webs 27blie coplanar with respective ones of the webs 20 and 21 when webs 27aare engaged in tracks 26. In assembly, two members as shown, member 27is slid into the tracks 26 of the two members, and thereby joins thesame in side-by-side parallel relation. The connector member 27, beingof thermally insulating material, provides a barrier reducing thetransmission of heat from one member to another in installations, forexample, building walls, where the two members are exposed respectivelyto the outside atmosphere and a heated inside atmosphere inside thebuilding. Altematively, a non-thermally insulated structure of similarconfiguration can be provided by having a structure wherein the membersare permanently connected, eliminating the connector 27 and tracks 26.

Also in FIG. 8 an assembly of two members designated generally by theletter A and a further assembly of two members designated generally bythe letter B are shown connected at right angles to one another.

To prepare the members for interconnection at right angles to oneanother requires basically three operations, namely:.

a. forming slots in flanges 24 of one member;

b. removing portions of flanges 24 in the other member to be connectedthereto; and

c. striking out tabs from flanges 23 in the abovementioned other member.The members in assembly A each have two slots 29 cut in each of theirflanges 24, each of the slots 29 having a width slightly greater thanthe thickness of one of the webs 20 and 21, the two slots 29 in eachflange 24 being spaced along the respective flange 24 a distancesubstantially the same as the distance between the webs 20 and 21 ofmember B. Each slot 29 in one of flanges 24 extends coplanar with acorresponding slot 29 in the other of flanges 24. With this arrangement,the webs 20 and 21 of a member in assembly B can fit within twocorresponding slots 29, one in each of the flanges 24 of a member inassembly A.

Each member of assembly B is prepared for connection to a respective oneof the members of assembly A by removing portions of flanges 24 at theend adjacent the end of assembly B to be joined to assembly A and a tab23a is formed in each of its flanges 23. Each tab 23a is struck out ofand extends outwardly from the plane of its respective flange 23 andprovides an edge 23c spaced from the end of assembly B a distance equalto the. spacing of ledges 25 from the webs 20 of the members of assemblyA. To interconnect the assemblies A and B each of the webs 20 and 21 ofeach member of assembly B is inserted into a respective pair ofcorresponding slots 29 in the flanges 24 of a respective one of themembers of assembly A, with flanges 23 of each member of assembly Bfitting between flanges 24 of a respective one of the members ofassembly A. The members are then pushed together. Engagement of tabs 23awith flanges 24 displaces the tabs into the planes of flanges 23 untilcomplete engagement is achieved, whereupon tabs 23a resume their normalpositions wherein their edges engage with ledges 25 of flanges 24 tolock the two members A and B in assembled relation. The tabs 23a andledges 25 therefore define respective coupling means on the respectiveflanges 23 and 24.

It will be apparent that the coupling means do not necessarily have tobe as shown in FIG. 8. The function of the coupling means could equallywell be provided by other forms of deformation or projection in flanges23 and 24. In one embodiment, tabs 23a are replaced by a plurality ofserrations on the outer faces of flanges 23. In this case it is alsopreferred to replace ledges 25 with a plurality of longitudinallyextending serrations engageable by the serrations on flanges 23. With anar rangement of this nature, an assembled structure may be readilydismantled by merely pulling the parts away from one another.

The members will usually be formed of relatively soft extruded material,such as aluminum or a suitable plastie, and in many applications it willbe possible to cut and deform the flanges 23 to provide tabs 23a at theconstruction site just prior to assembly, a tool (not shown) beingprovided for this purpose which is manually operable to exert sufficientcutting force to displace the tabs 23a out of the planes of flanges 23.Although FIG. 8 illustrates the structural members as disposed at rightangles to one another, it will also be apparent that they can bedisposed at any other angle transverse to one another, the mating facesbeing cut at the appropriate angles, as will the slots 29 in flanges 24of one of the members into which the other member fits.

Particular reference is now made to FIGS. 1, 9 and 10 to show the mannerin which the structural member can be employed. It will be seen fromFIG. 10 that the base member 11 comprises two members in accordance withFIG. 5 connected together by thermally insulating member 27 and fittedinto a channel 29, which channel is in turn fastened directly to thefoundation 10. The sill members 13 and the stud members 12 each comprisethe cross-section described with reference to FIG. 7 and have two pairsof flanges 23 and two pairs of flanges 24 extending from the respectivewebs 20 and 21 thereof, Each of wall panels 19 has its edges embedded ina respective strip of compressible material 30, these strips beingpressed into the spaces between respective pairs of flanges 24, wherethey are retained by retaining edges 25.

It will be seen from the upper part of FIG. 10 that flanges 24 can alsoserve as tracks for the mounting thereon of sliding windows constitutedby a glass sheet or sheets 18. Each sheet has its edges embedded instrips of resilient material 31, which are in turn engaged incorresponding recesses in a member 32 of special particular section. Themember 32 engaged on the lower edge of the glass sheet 18 is providedwith suitable bearing members 33 on the top edge of a flange 24 with lowsliding friction between them, while the member engaged on the upperedge of the glass is provided with strips of bearing sealing material 34which engage the side walls of the corresponding flange 24. Thestructure shown in FIG. 10 is effectively a four track window unitwherein each flange 24 could be provided with a sliding window and/orscreen combination. The vertical edges of the window pane 18 arepreferably provided with members similar to member 32 on the top edge ofthe pane for engagement with the respective flanges 24 of studs 12.

In a further embodiment, glass panes can be mounted in a similar mannerto the mounting of panels 19, with bearing members replacing thecompressible material 30 if so desired. To facilitate installation insuch instances one flange 24 on one member may have a greater dimensionthan the other, as measured from the web.

For use as a thermally insulated fixed pane window, one of the flanges24 of each of the members may be provided with an additional ledge 25extending oppositely to those shown in FIG. 10 and towards the othermember whereby a strip of material such as strip 30 may be held underthe additional ledges 25 and over the thermally insulating element 27 sothat a thermal pane may be installed coplanar with the thermallyinsulating element 27.

It will be understood that for special uses the flanges 24 of a membermay be omitted, the member therefore having a completely smooth exteriorside, and being particularly suited for use, for example, as a doorframe in which a door unit 16 (see FIG. 1) is mounted.

FIG. 9 shows one way in which a corner junction may be formed, whereintwo adjacent studs 12 of the same crossseetion as the floor and topplate members are joined at their abutting corners by means of avertical angle member 36. Other vertical recess holding mem-. bers 37are fastened to the flat faces of the vertical studs and provided withrespective vertical slots in which generally L-shaped corner member 38has returned edge portions 39 engaged and retained. It will be seentherefore that the assembly of such comers is a very quick and simpleoperation.

FIGS. 11 and 12 show the application of a structural member inaccordance with the present invention to the construction of a desk,wherein six vertical members 40 are used with interconnecting panels 41.A

tween the flanges 24 and can be pre-cut to slide vertically therein soas to be retained therein by the ledges 25. The tabs 23a are preformedto retain the top plate 43 when it is inserted therein.

The corner member 40 illustrated in FIG. 12 has general purposeapplication and it will be seen that the cross-section of this comermember 40 is that described with respect to FIG. 6.

Although in most of the embodiments illustrated flanges 23 are disposedinternally of the structural members with flanges 24 disposed externallythereof, other embodiments are envisaged which reverse this arrangement.

I claim:

1. An extruded structural member including an elongated structuralelement with two longitudinally extending side faces directed away fromone another, a pair of spaced apart longitudinally extending firstflanges integral with said element and projecting from one of the sidefaces thereof and a pair of spaced apart longitudinally extending secondflanges integral with said element and projecting from the other sideface thereof, with said first flanges having inner mating faces spacedapart a first predetermined distance and said second flanges havingouter mating faces spaced apart by said first predetermined distancesuch that the second flanges of one such member will fit slidably between the first flanges of another such member and with each flange ofone of said pairs of flanges having a ledge in its mating face, theledges extending the length of the flange facing towards the adjacentside face of the member and spaced therefrom a second predetermineddistance throughout the length of the flange, each flange of the otherpair of flanges having a resilient projection integral therewith,projecting from its mating face, each such projection having a free edgespaced from an end of the structural element by said secondpredetermined distance, facing away from said end and extending acrossthe associated mating faces in a direction transversely to said sidefaces of said structural element so that in assembling two suchstructural members with said end of one abutting against said one sideface of the other, the edges of the resilient projections of the onewill engage under the ledges of the other to hold the two memberstogether at a predetermined angular relationship.

2. The structural member of claim 1 wherein said ledges are formed insaid inner mating faces of said first flanges, and said projectionsproject from the outer mating faces of the second flanges.

3. The structural member of claim 2 wherein said structural element isof hollow rectangular crosssection and includes a first web having saidtwo side faces and a diametrically opposed second web, said firstflanges projecting from the outwardly directed one of said side faces ofsaid first web and the second flanges projecting from the inwardlydirected one of said side faces of said first web, said member furtherincluding a pair of spaced apart longitudinally extending third flangesintegral with said structural element projecting inwardly from saidsecond web, each said third flange being aligned with a respective oneof said second flanges and a resilient projection integral therewith,projecting from a mating face thereof, the projections having free edgesspaced from said end of the structural element by said secondpredetermined distance, facing away from said end and extending acrossthe associated mating faces in a direction transversely to said sidefaces of said structural element, said member also including a pair ofspaced apart longitudinally extending fourth flanges projectingoutwardly from said second web, said fourth flanges having the sameconfiguration as and being aligned with said first flanges.

4. The structural member of claim 2 wherein said structural element isof hollow rectangular cross section and includes a first web having saidtwo side faces, a diametrically opposed second web and a third webconnecting said first and second webs, the first flanges projecting fromthe outwardly directed one of said side faces of said first web and thesecond flanges projecting from the inwardly facing one of said sidefaces of said first web, said member further including a pair of spacedapart longitudinally extending third flanges projecting inwardly fromsaid second web, each said third flange being aligned with a respectiveone of said second flanges and a resilient projection integral therewithand projecting from an outer mating face thereof, the projections havingfree edges spaced from said end of the structural element by said secondprede terrnined distance, facing away from said end and extending acrossthe associated mating faces in a direction transversely to said sidefaces of said structural element, said member also including a pair ofspaced apart longitudinally extending fourth flanges projectingoutwardly from said third web and being substantially the same as saidfirst flanges.

5.The structural member of claim 2 wherein said structural element issubstantially L-shaped in crosssection including a first web having saidtwo side faces and a second web integral with said first web andextending angularly away therefrom.

6. The structural member of claim 2 wherein said projections comprisedeformed portions of said second flanges.

7. The structural member of claim 6 wherein said deformed portions areresiliently displaceable tabs.

8. The structural member of claim 2 wherein said structural element issubstantially U-shaped in crosssection and wherein one leg of said U isa first web having said two opposed side faces, the second flangesprojecting inwardly of the U from said first web and the first flangesprojecting outwardly of the U from the first web, the other leg of saidU comprising a second web having integral therewith a pair of spacedapart longitudinally extending third flanges projecting inwardly of saidU from said second web, each said third flange being aligned with arespective one of the second flanges and having a resilient projectionintegral therewith, projecting from an outer mating face thereof, theprojections having free edges spaced from said end of the structuralelement by said second predetermined distance, facing away from said endand extending across the associated mating faces in a directiontransversely to said side faces of said structural element.

9. The structural member of claim 8 including a pair of spaced apartlongitudinally extending fourth flanges integral with said structuralelement and projecting outwardly of said U from said second web, saidfourth flanges having the same configuration as and being aligned withsaid first flanges.

10. The structural member of claim 8 wherein the free ends of the legsof said U are each provided with a substantially L-shaped longitudinallyextending track structure.

11. The structural member of claim 9 wherein the free ends of the legsof said U are each provided with a substantially L-shaped longitudinallyextending track structure.

1. An extruded structural member including an elongated structuralelement with two longitudinally extending side faces directed away fromone another, a pair of spaced apart longitudinally extending firstflanges integral with said element and projecting from one of the sidefaces thereof and a pair of spaced apart longitudinally extending secondflanges integral with said element and projecting from the other sideface thereof, with said first flanges having inner mating faces spacedapart a first predetermined distance and said second flanges havingouter mating faces spaced apart by said first predetermined distancesuch that the second flanges of one such member will fit slidablybetween the first flanges of another such member and with each flange ofone of said pairs of flanges having a ledge in its mating face, theledges extending the length of the flange facing towards the adjacentside face of the member and spaced therefrom a second predetermineddistance throughout the length of the flange, each flange of the otherpair of flanges having a resilient projection integral therewith,projecting from its mating face, each such projection having a free edgespaced from an end of the structural element by said secondpredetermined distance, facing away from said end and extending acrossthe associated mating faces in a direction transversely to said sidefaces of said structural element so that in assembling two suchstructural members with said end of one abutting against said one sideface of the other, the edges of the resilient projections of the onewill engage under the ledges of the other to hold the two memberstogether at a predetermined angular relationship.
 2. The structuralmember of claim 1 wherein said ledges are formed in said inner matingfaces of said fIrst flanges, and said projections project from the outermating faces of the second flanges.
 3. The structural member of claim 2wherein said structural element is of hollow rectangular cross-sectionand includes a first web having said two side faces and a diametricallyopposed second web, said first flanges projecting from the outwardlydirected one of said side faces of said first web and the second flangesprojecting from the inwardly directed one of said side faces of saidfirst web, said member further including a pair of spaced apartlongitudinally extending third flanges integral with said structuralelement projecting inwardly from said second web, each said third flangebeing aligned with a respective one of said second flanges and aresilient projection integral therewith, projecting from a mating facethereof, the projections having free edges spaced from said end of thestructural element by said second predetermined distance, facing awayfrom said end and extending across the associated mating faces in adirection transversely to said side faces of said structural element,said member also including a pair of spaced apart longitudinallyextending fourth flanges projecting outwardly from said second web, saidfourth flanges having the same configuration as and being aligned withsaid first flanges.
 4. The structural member of claim 2 wherein saidstructural element is of hollow rectangular cross-section and includes afirst web having said two side faces, a diametrically opposed second weband a third web connecting said first and second webs, the first flangesprojecting from the outwardly directed one of said side faces of saidfirst web and the second flanges projecting from the inwardly facing oneof said side faces of said first web, said member further including apair of spaced apart longitudinally extending third flanges projectinginwardly from said second web, each said third flange being aligned witha respective one of said second flanges and a resilient projectionintegral therewith and projecting from an outer mating face thereof, theprojections having free edges spaced from said end of the structuralelement by said second predetermined distance, facing away from said endand extending across the associated mating faces in a directiontransversely to said side faces of said structural element, said memberalso including a pair of spaced apart longitudinally extending fourthflanges projecting outwardly from said third web and being substantiallythe same as said first flanges.
 5. The structural member of claim 2wherein said structural element is substantially L-shaped incross-section including a first web having said two side faces and asecond web integral with said first web and extending angularly awaytherefrom.
 6. The structural member of claim 2 wherein said projectionscomprise deformed portions of said second flanges.
 7. The structuralmember of claim 6 wherein said deformed portions are resilientlydisplaceable tabs.
 8. The structural member of claim 2 wherein saidstructural element is substantially U-shaped in cross-section andwherein one leg of said U is a first web having said two opposed sidefaces, the second flanges projecting inwardly of the U from said firstweb and the first flanges projecting outwardly of the U from the firstweb, the other leg of said U comprising a second web having integraltherewith a pair of spaced apart longitudinally extending third flangesprojecting inwardly of said U from said second web, each said thirdflange being aligned with a respective one of the second flanges andhaving a resilient projection integral therewith, projecting from anouter mating face thereof, the projections having free edges spaced fromsaid end of the structural element by said second predetermineddistance, facing away from said end and extending across the associatedmating faces in a direction transversely to said side faces of saidstructural element.
 9. The structural member of claim 8 including a pairof spaced apart longitudinally extending fourth flanges integral withsaid structural element and projecting outwardly of said U from saidsecond web, said fourth flanges having the same configuration as andbeing aligned with said first flanges.
 10. The structural member ofclaim 8 wherein the free ends of the legs of said U are each providedwith a substantially L-shaped longitudinally extending track structure.11. The structural member of claim 9 wherein the free ends of the legsof said U are each provided with a substantially L-shaped longitudinallyextending track structure.